If you pay attention to United States politics you have probably noticed that mathematics is currently enjoying a rare moment of relevance. You probably also know this is not happening because all of a sudden politicians have decided that mathematics is clearly the coolest thing in the world, even though it clearly is, but instead because *gerrymandering* has become one of the major issues du jour.

For those of you lucky enough not to know what gerrymandering is, let me give you a quick prĂ©cis. Named after Elbridge Gerry – it should be pronounced like *Gary* and not *Jerry* – and a congressional district which slightly resembled a salamander he signed into law as the governor of Massachusetts, gerrymandering has come to be the blanket term for the redrawing of political districts in the United States in a way that provides political gain for the party conducting the redrawing. This is primarily done through either *packing*, drawing a district so all of your opponents’ votes are concentrated in a small number of districts and therefore can not meaningfully affect others, or *cracking*, splitting up the opponents’ votes among many different districts so they have less influence on any of them. This has generally been considered to be totally legitimate, and smart, political maneuvering in the US and upheld as legal in the courts, unless it can be proven the gerrymandering was done based on race and not on partisanship. (C*orrected from ‘based on partisanship and not on race’ on 27/02/2018*)

The reason gerrymandering is such a hot topic is because the courts might just be changing their views regarding partisan gerrymandering, and a big factor behind this is mathematics. There was an argument in front of the supreme court, in the case of *Gill v. Whitford* late last year about partisan gerrymandering in my home state of Wisconsin, which had mathematics as a central pillar in the arguments against the current district lines. Even more recently the Pennsylvania Supreme Court threw out their current districts and demanded they be redrawn, and while I am not sure if mathematics played a large role in them getting thrown out it certainly will when they are redrawn.

As gerrymandering is enjoying its moment in the sun, it is only fair the mathematician playing the biggest role in changing how it is all being thought about is called Moon. Moon Duchin is an Associate Professor at Tufts University and the creator of the Metric Geometry and Gerrymandering Group which, through a series of conferences, is applying cutting-edge mathematics to the redistricting problem, training mathematicians to be expert witnesses on gerrymandering for court proceedings, and providing teachers with lesson plans and guidance on how to implement them (there is one more conference in California coming up in March and a big workshop happening in August if you want to get involved).

The really big news though is, as of January 26 Duchin is working as a consultant for Governor Wolf in Pennsylvania, with the job of helping to make sure their redrawn congressional district map is fair. I have had the joy of talking to Moon for my podcast Relatively Prime about her work with the MGGG and watched her give a talk about gerrymandering at the 2018 Joint Mathematics Meeting. I do not think I have ever seen a more enraptured audience at a mathematics conference, there were a lot of people in the room and each and every one of them was paying attention. I can not think of a better person from a mathematical ability perspective, as well as a public engagement one, to be the face of this for mathematics.

It is too bad it has taken something so awful as gerrymandering to get mathematics a seat at the table in US political discourse, and even though I have spent a huge amount of my life trying to convince people mathematics is something we should all care about I would happily not have people talk about it if it meant we had no gerrymandering. That said, I am glad we have mathematicians like Moon Duchin who are willing to take this battle on in front of not only the mathematical community but an ever increasing portion of the politically engaged public, not to mention Governor Wolf and lawyers like those in *Gill v. Whitford* who are willing to reach past their comfort zone and let mathematics play a central role in their work. There is not going to be a clean, perfect solution to all of this, but hopefully with mathematicians like Moon involved in this it will end up a lot better than where it is now.

“upheld as legal in the courts, unless it can be proven the gerrymandering was done based on partisanship and not on race.”

The other way around, right?

Joshua, you are correct. That was a mistake on my part. I have corrected the post, thanks for catching the error.